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1.
Cell ; 185(25): 4717-4736.e25, 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36493752

RESUMEN

Adult mammalian skin wounds heal by forming fibrotic scars. We report that full-thickness injuries of reindeer antler skin (velvet) regenerate, whereas back skin forms fibrotic scar. Single-cell multi-omics reveal that uninjured velvet fibroblasts resemble human fetal fibroblasts, whereas back skin fibroblasts express inflammatory mediators mimicking pro-fibrotic adult human and rodent fibroblasts. Consequently, injury elicits site-specific immune responses: back skin fibroblasts amplify myeloid infiltration and maturation during repair, whereas velvet fibroblasts adopt an immunosuppressive phenotype that restricts leukocyte recruitment and hastens immune resolution. Ectopic transplantation of velvet to scar-forming back skin is initially regenerative, but progressively transitions to a fibrotic phenotype akin to the scarless fetal-to-scar-forming transition reported in humans. Skin regeneration is diminished by intensifying, or enhanced by neutralizing, these pathologic fibroblast-immune interactions. Reindeer represent a powerful comparative model for interrogating divergent wound healing outcomes, and our results nominate decoupling of fibroblast-immune interactions as a promising approach to mitigate scar.


Asunto(s)
Reno , Cicatrización de Heridas , Adulto , Animales , Humanos , Cicatriz/patología , Fibroblastos/patología , Trasplante de Piel , Piel/patología , Feto/patología
2.
Proc Natl Acad Sci U S A ; 119(32): e2111726119, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35914162

RESUMEN

A large number of neutrophils infiltrate the lymph node (LN) within 4 h after Staphylococcus aureus skin infection (4 h postinfection [hpi]) and prevent systemic S. aureus dissemination. It is not clear how infection in the skin can remotely and effectively recruit neutrophils to the LN. Here, we found that lymphatic vessel occlusion substantially reduced neutrophil recruitment to the LN. Lymphatic vessels effectively transported bacteria and proinflammatory chemokines (i.e., Chemokine [C-X-C motif] motif 1 [CXCL1] and CXCL2) to the LN. However, in the absence of lymph flow, S. aureus alone in the LN was insufficient to recruit neutrophils to the LN at 4 hpi. Instead, lymph flow facilitated the earliest neutrophil recruitment to the LN by delivering chemokines (i.e., CXCL1, CXCL2) from the site of infection. Lymphatic dysfunction is often found during inflammation. During oxazolone (OX)-induced skin inflammation, CXCL1/2 in the LN was reduced after infection. The interrupted LN conduits further disrupted the flow of lymph and impeded its communication with high endothelial venules (HEVs), resulting in impaired neutrophil migration. The impaired neutrophil interaction with bacteria contributed to persistent infection in the LN. Our studies showed that both the flow of lymph from lymphatic vessels to the LN and the distribution of lymph in the LN are critical to ensure optimal neutrophil migration and timely innate immune protection in S. aureus infection.


Asunto(s)
Quimiocinas , Infiltración Neutrófila , Enfermedades Cutáneas Bacterianas , Infecciones Estafilocócicas , Animales , Quimiocinas/inmunología , Inmunidad Innata , Inflamación/patología , Linfa/inmunología , Ganglios Linfáticos/citología , Ratones , Ratones Endogámicos C57BL , Neutrófilos/citología , Enfermedades Cutáneas Bacterianas/inmunología , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus
3.
Pharmacol Rev ; 74(3): 712-768, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35738680

RESUMEN

The first matrix metalloproteinase (MMP) was discovered in 1962 from the tail of a tadpole by its ability to degrade collagen. As their name suggests, matrix metalloproteinases are proteases capable of remodeling the extracellular matrix. More recently, MMPs have been demonstrated to play numerous additional biologic roles in cell signaling, immune regulation, and transcriptional control, all of which are unrelated to the degradation of the extracellular matrix. In this review, we will present milestones and major discoveries of MMP research, including various clinical trials for the use of MMP inhibitors. We will discuss the reasons behind the failures of most MMP inhibitors for the treatment of cancer and inflammatory diseases. There are still misconceptions about the pathophysiological roles of MMPs and the best strategies to inhibit their detrimental functions. This review aims to discuss MMPs in preclinical models and human pathologies. We will discuss new biochemical tools to track their proteolytic activity in vivo and ex vivo, in addition to future pharmacological alternatives to inhibit their detrimental functions in diseases. SIGNIFICANCE STATEMENT: Matrix metalloproteinases (MMPs) have been implicated in most inflammatory, autoimmune, cancers, and pathogen-mediated diseases. Initially overlooked, MMP contributions can be both beneficial and detrimental in disease progression and resolution. Thousands of MMP substrates have been suggested, and a few hundred have been validated. After more than 60 years of MMP research, there remain intriguing enigmas to solve regarding their biological functions in diseases.


Asunto(s)
Inhibidores de la Metaloproteinasa de la Matriz , Neoplasias , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Humanos , Inhibidores de la Metaloproteinasa de la Matriz/metabolismo , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/uso terapéutico , Metaloproteinasas de la Matriz/metabolismo , Metaloproteinasas de la Matriz/uso terapéutico , Neoplasias/metabolismo , Proteolisis
4.
Traffic ; 23(11): 538-553, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36117140

RESUMEN

Those who study macrophage biology struggle with the decision whether to utilize primary macrophages derived directly from mice or opt for the convenience and genetic tractability of immortalized macrophage-like cell lines in in vitro studies. Particularly when it comes to studying phagocytosis and phagosomal maturation-a signature cellular process of the macrophage-many commonly used cell lines are not representative of what occurs in primary macrophages. A system developed by Mark Kamps' group, that utilizes conditionally constitutive activity of Hox transcription factors (Hoxb8 and Hoxa9) to immortalize differentiation-competent myeloid cell progenitors of mice, offers an alternative to the macrophage/macrophage-like dichotomy. In this resource, we will review the use of Hoxb8 and Hoxa9 as hematopoietic regulators to conditionally immortalize murine hematopoietic progenitor cells which retain their ability to differentiate into many functional immune cell types including macrophages, neutrophils, basophils, osteoclasts, eosinophils, dendritic cells, as well as limited potential for the generation of lymphocytes. We further demonstrate that the use of macrophages derived from Hoxb8/Hoxa9 immortalized progenitors and their similarities to bone marrow-derived macrophages. To supplement the existing data, mass spectrometry-based proteomics, flow cytometry, cytology, and in vitro phagosomal assays were conducted on macrophages derived from Hoxb8 immortalized progenitors and compared to bone marrow-derived macrophages and the macrophage-like cell line J774. We additionally propose the use of a standardized nomenclature to describe cells derived from the Hoxb8/Hoxa9 system in anticipation of their expanded use in the study of leukocyte cell biology.


Asunto(s)
Células Madre Hematopoyéticas , Macrófagos , Animales , Diferenciación Celular , Macrófagos/metabolismo , Ratones , Factores de Transcripción/metabolismo
5.
Ann Hum Genet ; 88(2): 113-125, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37807935

RESUMEN

INTRODUCTION: Next generation sequencing technology has greatly reduced the cost and time required for sequencing a genome. An approach that is rapidly being adopted as an alternative method for CNV analysis is the low-pass whole genome sequencing (LP-WGS). Here, we evaluated the performance of LP-WGS to detect copy number variants (CNVs) in clinical cytogenetics. MATERIALS AND METHODS: DNA samples with known CNVs detected by chromosomal microarray analyses (CMA) were selected for comparison and used as positive controls; our panel included 44 DNA samples (12 prenatal and 32 postnatal), comprising a total of 55 chromosome imbalances. The selected cases were chosen to provide a wide range of clinically relevant CNVs, the vast majority being associated with intellectual disability or recognizable syndromes. The chromosome imbalances ranged in size from 75 kb to 90.3 Mb, including aneuploidies and two cases of mosaicism. RESULTS: All CNVs were successfully detected by LP-WGS, showing a high level of consistency and robust performance of the sequencing method. Notably, the size of chromosome imbalances detected by CMA and LP-WGS were compatible between the two different platforms, which indicates that the resolution and sensitivity of the LP-WGS approach are at least similar to those provided by CMA. DISCUSSION: Our data show the potential use of LP-WGS to detect CNVs in clinical diagnosis and confirm the method as an alternative for chromosome imbalances detection. The diagnostic effectiveness and feasibility of LP-WGS, in this technical validation study, were evidenced by a clinically representative dataset of CNVs that allowed a systematic assessment of the detection power and the accuracy of the sequencing approach. Further, since the software used in this study is commercially available, the method can easily be tested and implemented in a routine diagnostic setting.


Asunto(s)
Aneuploidia , Variaciones en el Número de Copia de ADN , Embarazo , Femenino , Humanos , Análisis Costo-Beneficio , Secuenciación Completa del Genoma/métodos , ADN
6.
Am J Med Genet A ; 194(11): e63802, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38924610

RESUMEN

Low-pass whole genome sequencing (LP-WGS) has been applied as alternative method to detect copy number variants (CNVs) in the clinical setting. Compared with chromosomal microarray analysis (CMA), the sequencing-based approach provides a similar resolution of CNV detection at a lower cost. In this study, we assessed the efficiency and reliability of LP-WGS as a more affordable alternative to CMA. A total of 1363 patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies were enrolled. Those patients were referred from 15 nonprofit organizations and university centers located in different states in Brazil. The analysis of LP-WGS at 1x coverage (>50kb) revealed a positive testing result in 22% of the cases (304/1363), in which 219 and 85 correspond to pathogenic/likely pathogenic (P/LP) CNVs and variants of uncertain significance (VUS), respectively. The 16% (219/1363) diagnostic yield observed in our cohort is comparable to the 15%-20% reported for CMA in the literature. The use of commercial software, as demonstrated in this study, simplifies the implementation of the test in clinical settings. Particularly for countries like Brazil, where the cost of CMA presents a substantial barrier to most of the population, LP-WGS emerges as a cost-effective alternative for investigating copy number changes in cytogenetics.


Asunto(s)
Variaciones en el Número de Copia de ADN , Secuenciación Completa del Genoma , Humanos , Variaciones en el Número de Copia de ADN/genética , Secuenciación Completa del Genoma/economía , Secuenciación Completa del Genoma/métodos , Brasil , Masculino , Femenino , Niño , Discapacidad Intelectual/genética , Discapacidad Intelectual/diagnóstico , Análisis Costo-Beneficio , Análisis por Micromatrices/economía , Análisis por Micromatrices/métodos , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/diagnóstico , Preescolar , Anomalías Múltiples/genética , Anomalías Múltiples/diagnóstico , Países en Desarrollo , Adolescente , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/diagnóstico , Pruebas Genéticas/economía , Pruebas Genéticas/métodos
7.
World J Surg Oncol ; 22(1): 217, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39180093

RESUMEN

BACKGROUND: Pancreatic head cancer patients who undergo pancreatoduodenectomy (PD) often experience disease recurrence, frequently associated with a positive margin status (R1). Total mesopancreas excision (TMpE) has emerged as a potential approach to increase surgical radicality and minimize locoregional recurrence. However, its effectiveness and safety remain under evaluation. METHODS: We conducted a systematic review and meta-analysis to synthesize current evidence on TMpE outcomes. A systematic search of MEDLINE, EMBASE, Cochrane, and Web of Science databases was conducted up to March 2024 to identify studies comparing TMpE with standard pancreatoduodenectomy (sPD). The risk ratio (RR) or mean difference (MD) was pooled using a random effects model. RESULTS: From 452 studies identified, 9 studies with a total of 738 patients were included, with 361 (49%) undergoing TMpE. TMpE significantly improved the R0 resection rate (RR 1.24; 95% CI 1.11-1.38; P < 0.05), reduced blood loss (MD -143.70 ml; 95% CI -247.92, -39.49; P < 0.05), and increased lymph node harvest (MD 7.27 nodes; 95% CI 4.81, 9.73; P < 0.05). No significant differences were observed in hospital stay, postoperative complications, or mortality between TMpE and sPD. TMpE also significantly reduced overall recurrence (RR 0.53; 95% CI 0.35-0.81; P < 0.05) and local recurrence (RR 0.39; 95% CI 0.24-0.63; P < 0.05). Additionally, the risk of pancreatic fistula was lower in the TMpE group (RR 0.66; 95% CI 0.52-0.85; P < 0.05). CONCLUSION: Total mesopancreas excision significantly increases the R0 resection rate and reduces locoregional recurrence while maintaining an acceptable safety profile when compared with standard pancreatoduodenectomy. Further prospective randomized studies are warranted to determine the optimal surgical approach for total mesopancreatic resection.


Asunto(s)
Neoplasias Pancreáticas , Pancreaticoduodenectomía , Humanos , Pancreaticoduodenectomía/métodos , Pancreaticoduodenectomía/efectos adversos , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/epidemiología , Pronóstico , Márgenes de Escisión
8.
Am Heart J ; 264: 97-105, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37330162

RESUMEN

BACKGROUND: It is estimated that atrial fibrillation (AF) affects approximately 1.5 million people in Brazil; however, epidemiological data are limited. We sought to evaluate the characteristics, treatment patterns, and clinical outcomes in patients with AF in Brazil by creating the first nationwide prospective registry. METHODS: RECALL was a multicenter, prospective registry that included and followed for 1 year 4,585 patients with AF at 89 sites across Brazil from April 2012 to August 2019. Patient characteristics, concomitant medication use, and clinical outcomes were analyzed using descriptive statistics and multivariable models. RESULTS: Of 4,585 patients enrolled, the median age was 70 (61, 78) years, 46% were women, and 53.8% had permanent AF. Only 4.4% of patients had a history of previous AF ablation and 25.2% had a previous cardioversion. The mean (SD) CHA2DS2-VASc score was 3.2 (1.6); median HAS-BLED score was 2 (2, 3). At baseline, 22% were not on anticoagulants. Of those taking anticoagulants, 62.6% were taking vitamin K antagonists and 37.4% were taking direct oral anticoagulants. The primary reasons for not using an oral anticoagulant were physician judgment (24.6%) and difficulty in controlling (14.7%) or performing (9.9%) INR. Mean (SD) TTR for the study period was 49.5% (27.5). During follow-up, the use of anticoagulants and INR in the therapeutic range increased to 87.1% and 59.1%, respectively. The rates/100 patient-years of death, hospitalization due to AF, AF ablation, cardioversion, stroke, systemic embolism, and major bleeding were 5.76 (5.12-6.47), 15.8 (14.6-17.0), 5.0 (4.4-5.7), 1.8 (1.4-2.2), 2.77 (2.32-3.32), 1.01 (0.75-1.36), and 2.21 (1.81-2.70). Older age, permanent AF, New York Heart Association class III/IV, chronic kidney disease, peripheral arterial disease, stroke, chronic obstructive pulmonary disease, and dementia were independently associated with increased mortality while the use of anticoagulant was associated with lower risk of death. CONCLUSIONS: RECALL represents the largest prospective registry of patients with AF in Latin America. Our findings highlight important gaps in treatment, which can inform clinical practice and guide future interventions to improve the care of these patients.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Femenino , Anciano , Masculino , Fibrilación Atrial/epidemiología , Fibrilación Atrial/terapia , Fibrilación Atrial/complicaciones , Brasil/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Anticoagulantes , Hemorragia/inducido químicamente , Sistema de Registros
9.
Genomics ; 114(2): 110287, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35131478

RESUMEN

We sequenced 13 Neisseria gonorrhoeae isolates exhibiting distinct susceptibility profiles and which were recovered over 12 years in the metropolitan region of São Paulo, Brazil. Whole Genome Sequencing (WGS) was performed on an Illumina MiSeq™ 2 × 300 bp paired-end reads. Bioinformatics analyses were carried out using CGE, PATRIC, and BLAST databases for manual curation of obtained genomes. Multilocus sequence typing (MLST) analysis identified seven STs, namely ST1580, ST1590, ST1901, ST1902, ST8161, ST9363, and ST15640. Moreover, a diversity of mutations was observed in MtrR/G45D-A39T, PIB/G120K-A121S, and PBP1/L421P. Mutations associated with sulfonamides (DHPS/R228S) and rifampicin (RNAP/H552N) were also detected, as well as tetracycline resistance determinants, namely rpsJ/V57M and tet(M). The results presented herein can contribute to the knowledge of N. gonorrhoeae strains circulating in Sao Paulo, Brazil.


Asunto(s)
Gonorrea , Neisseria gonorrhoeae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Brasil , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana/genética , Gonorrea/tratamiento farmacológico , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Neisseria gonorrhoeae/genética
10.
J Virol ; 95(23): e0112221, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34549980

RESUMEN

Chikungunya virus (CHIKV) and Mayaro virus (MAYV) are closely related members of the Semliki Forest virus antigenic complex classified as belonging to the genus Alphavirus of the family Togaviridae. These viruses cause human disease, with sudden fever and joint inflammation that can persist for long periods. CHIKV is the causative agent of large outbreaks worldwide, and MAYV infection represents a growing public health concern in Latin America, causing sporadic cases and geographically limited outbreaks. Considering the relationship between CHIKV and MAYV, the present study aimed to evaluate if preexisting CHIKV immunity protects against MAYV infection. Immunocompetent C57BL/6 mice were intraperitoneally infected with CHIKV and, 4 weeks later, they were infected with MAYV in their hind paw. We observed that the preexistence of CHIKV immunity conferred partial cross-protection against secondary MAYV infection, reducing disease severity, tissue viral load, and histopathological scores. Interestingly, CHIKV antibodies from humans and mice showed low cross-neutralization to MAYV, but neutralizing activity significantly increased after secondary infection. Furthermore, depletion of adaptive immune cells (CD4+ T, CD8+ T, and CD19+ B cells) did not alter the cross-protection phenotype, suggesting that distinct cell subsets or a combination of adaptive immune cells stimulated by CHIKV are responsible for the partial cross-protection against MAYV. The reduction of proinflammatory cytokines, such as interferon gamma (IFN-γ), in animals secondarily infected by MAYV, suggests a role for innate immunity in cross-protection. Our findings shed light on how preexisting immunity to arthritogenic alphaviruses may affect secondary infection, which may further develop relevant influence in disease outcome and viral transmission. IMPORTANCE Mosquito-borne viruses have a worldwide impact, especially in tropical climates. Chikungunya virus has been present mostly in developing countries, causing millions of infections, while Mayaro virus, a close relative, has been limited to the Caribbean and tropical regions of Latin America. The potential emergence and spread of Mayaro virus to other high-risk areas have increased the scientific community's attention to an imminent worldwide epidemic. Here, we designed an experimental protocol of chikungunya and Mayaro virus mouse infection, which develops a measurable and quantifiable disease that allows us to make inferences about potential immunological effects during secondary virus infection. Our results demonstrate that previous chikungunya virus infection is able to reduce the severity of clinical outcomes during secondary Mayaro infection. We provide scientific understanding of immunological features during secondary infection with the closely related virus, thus assisting in better comprehending viral transmission and the pathological outcome of these diseases.


Asunto(s)
Infecciones por Alphavirus/inmunología , Infecciones por Alphavirus/prevención & control , Virus Chikungunya/inmunología , Protección Cruzada/inmunología , Alphavirus/inmunología , Infecciones por Alphavirus/patología , Animales , Anticuerpos Antivirales/inmunología , Fiebre Chikungunya/virología , Modelos Animales de Enfermedad , Epidemias , Femenino , Inflamación , Ratones , Ratones Endogámicos C57BL , Carga Viral
12.
Clin Med Res ; 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36028283

RESUMEN

OBJECTIVE: The objective of this study was to identify, among the different anthropometric indicators, the one that shows higher discriminatory power for the prognosis of Obstructive Sleep Apnea Syndrome (OSAS). DESIGN: Observational cross-sectional study PARTICIPANTS: Obese individuals elective to bariatric surgery METHODS: A study based on data of 758 patients aged ≥ 21 years old, of both sexes, in the pre-operatory stage of the surgical procedure of gastric bypass. Obstructive sleep apnea and obstructive sleep hypopnea were evaluated and classified through the apnea-hypopnea index, which was obtained through the examination of polysomnography. Variables were divided into two groups: individuals with and without OSAS. As predictors, measures of body mass index (BMI), neck circumference (NC), and waist circumference (WC) were used. RESULTS: The area under the ROC curve was used to check the sensitivity and specificity. All evaluated anthropometric indicators showed statistical significance. WC: area of 0.62 (CI 95%: 0.58 - 0.67), NC: area of 0,68 (CI 95%: 0.64 - 0.72) and BMI: area of 0.58 (CI 95%: 0.54 - 0.63). CONCLUSION: The investigated anthropometric indicators performed as good predictors of OSAS. However, NC seems to be the best anthropometric indicator for the prognosis of OSAS in obese individuals when compared to BMI and WC.

13.
BMC Musculoskelet Disord ; 23(1): 992, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36401258

RESUMEN

BACKGROUND: Clavicle fractures account for approximately 5% of all fractures in adults and 75% of clavicle fractures occur in the midshaft. Shortening greater than two centimeters is an indicative of surgical treatment. Radiographic exams are often used to diagnose and evaluate clavicle fractures but computed tomography (CT) scan is currently considered the best method to assess these deformities and shortening. GOAL: 1- To investigate whether different methods of performing the radiographic exam interfere on the measurement of the fractured clavicle length. 2- Compare the clavicle length measurements obtained by the different radiographic exam methods with the CT scan measurements, used as a reference. MATERIALS AND METHODS: Twenty-five patients with acute (< 3 weeks) midshaft clavicle fracture were evaluated. Patients underwent six radiographic images: PA Thorax (standing and lying), AP Thorax (standing and lying) and at 10° cephalic tilt (standing and lying), and the computed tomography was used as reference. RESULTS: The mean length (cm) obtained were: 14,930 on CT scan, 14,860 on PA Thorax Standing, 14,955 on PA Thorax Lying, 14,896 on AP Thorax Standing, 14,960 AP Thorax Lying, 15,098 on 10° cephalic tilt Standing and 15,001 on 10° cephalic tilt Lying, (p > 0,05). CONCLUSION: 1- There is no significant statistical difference in the clavicle fracture length measurement among the variety of radiographic exam performances. 2- The method that comes closest to computed tomography results is the PA thorax incidence, with the patient in the lying position.


Asunto(s)
Clavícula , Fracturas Óseas , Humanos , Adulto , Clavícula/diagnóstico por imagen , Fracturas Óseas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Tórax
14.
Mem Inst Oswaldo Cruz ; 116: e210176, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35019069

RESUMEN

BACKGROUND: During routine Coronavirus disease 2019 (COVID-19) diagnosis, an unusually high viral load was detected by reverse transcription real-time polymerase chain reaction (RT-qPCR) in a nasopharyngeal swab sample collected from a patient with respiratory and neurological symptoms who rapidly succumbed to the disease. Therefore we sought to characterise the infection. OBJECTIVES: We aimed to determine and characterise the etiological agent responsible for the poor outcome. METHODS: Classical virological methods, such as plaque assay and plaque reduction neutralisation test combined with amplicon-based sequencing, as well as a viral metagenomic approach, were performed to characterise the etiological agents of the infection. FINDINGS: Plaque assay revealed two distinct plaque phenotypes, suggesting either the presence of two severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains or a productive coinfection of two different species of virus. Amplicon-based sequencing did not support the presence of any SARS-CoV-2 genetic variants that would explain the high viral load and suggested the presence of a single SARS-CoV-2 strain. Nonetheless, the viral metagenomic analysis revealed that Coronaviridae and Herpesviridae were the predominant virus families within the sample. This finding was confirmed by a plaque reduction neutralisation test and PCR. MAIN CONCLUSIONS: We characterised a productive coinfection of SARS-CoV-2 and Herpes simplex virus 1 (HSV-1) in a patient with severe symptoms that succumbed to the disease. Although we cannot establish the causal relationship between the coinfection and the severity of the clinical case, this work serves as a warning for future studies focused on the interplay between SARS-CoV-2 and HSV-1 coinfection and COVID-19 severity.


Asunto(s)
COVID-19 , Coinfección , Herpesvirus Humano 1 , Herpesvirus Humano 1/genética , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2
15.
An Acad Bras Cienc ; 94(4): e20210262, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35946750

RESUMEN

Cattle ranching is the primary land-use of deforested areas in the Brazilian Amazon. Deforestation precedes pasture establishment, implying tremendous amounts of greenhouse gas emissions caused by carbon stock losses. Despite several studies addressing carbon storage in forests, there is a lack of data regarding cultivated pastures. Hence, the estimation of greenhouse gas emissions associated with land-use change becomes uncertain. In this study, we assessed the carbon stock of cultivated pastures located in Rondônia, southwestern Brazilian Amazon. A total of 50 squared plots of 1 m² were randomly allocated in cattle ranching farms covered by Oxisols (Dystrophic Yellow and Dystrophic Red-Yellow Latosols). Carbon fraction ranged from 0.36 for belowground biomass to 0.45 gC.g-1 d.m. for aboveground biomass. The average total carbon stock was 5.17 MgC.ha-1, with non-significant differences when stratifying data by soil types. Considering data from the III Brazilian Inventory of Anthropogenic Emissions and Removals of Greenhouse Gases, our results suggested that land-use change from primary forests to cultivated pastures resulted in a loss of 192.54 MgC.ha-1, which corresponds to a net emission of 705.98 MgCO2eq.ha-1 to the atmosphere. This study provides valuable information to improve the Brazilian Inventory of Anthropogenic Emissions and Removals of Greenhouse Gases.


Asunto(s)
Carbono , Gases de Efecto Invernadero , Animales , Brasil , Carbono/análisis , Bovinos , Conservación de los Recursos Naturales , Bosques
16.
An Acad Bras Cienc ; 93(1): e20200511, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33759953

RESUMEN

Dynamic loads continue to draw the interest of structural engineers. The sources of these loads can be earthquakes, blast effects or transportation loads from railroads or highways. Especially for blast loads, terrorist attacks or military actions have caused many loses of lives and damages in several buildings. The verification of structural behavior is necessary to help designers to plan structures that support these loads and reduce damages. Although computer simulation with, specific software, have helped these designers, full-scale tests can provide valuable information about the real response of the structure. This paper presents damage diagram from ten full-scale field tests using approximately 2.70 kg of non-confined plastic bonded explosive against reinforced concrete slabs with different scaled distance, reinforcement ratio and concrete strength. The damage diagram is expected to be a help tool for designers to understand the effects of blast loads on slabs.


Asunto(s)
Materiales de Construcción , Terremotos , Simulación por Computador , Programas Informáticos
17.
Hum Mutat ; 41(4): 759-773, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31799751

RESUMEN

The TSC1 and TSC2 gene products interact to form the tuberous sclerosis complex (TSC), an important negative regulator of the mechanistic target of rapamycin complex 1 (TORC1). Inactivating mutations in TSC1 or TSC2 cause TSC, and the identification of a pathogenic TSC1 or TSC2 variant helps establish a diagnosis of TSC. However, it is not always clear whether TSC1 and TSC2 variants are inactivating. To determine whether TSC1 and TSC2 variants of uncertain clinical significance affect TSC complex function and cause TSC, in vitro assays of TORC1 activity can be employed. Here we combine genetic, functional, and structural approaches to try and classify a series of 15 TSC2 VUS. We investigated the effects of the variants on the formation of the TSC complex, on TORC1 activity and on TSC2 pre-mRNA splicing. In 13 cases (87%), the functional data supported the hypothesis that the identified TSC2 variant caused TSC. Our results illustrate the benefits and limitations of functional testing for TSC.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mutación , Fenotipo , Proteína 2 del Complejo de la Esclerosis Tuberosa/química , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética , Sustitución de Aminoácidos , Técnicas de Silenciamiento del Gen , Estudios de Asociación Genética/métodos , Genotipo , Humanos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Multimerización de Proteína , Empalme del ARN , Relación Estructura-Actividad , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo
18.
Biochemistry ; 59(3): 329-340, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31774660

RESUMEN

Legumain (asparaginyl endopeptidase) is the only protease with a preference for cleavage after asparagine residues. Increased legumain activity is a hallmark of inflammation, neurodegenerative diseases, and cancer, and legumain inhibitors have exhibited therapeutic effects in mouse models of these pathologies. Improved knowledge of its substrates and cellular functions is a requisite to further validation of legumain as a drug target. We, therefore, aimed to investigate the effects of legumain inhibition in macrophages using an unbiased and systematic approach. By shotgun proteomics, we identified 16 094 unique peptides in RAW264.7 cells. Among these, 326 unique peptides were upregulated in response to legumain inhibition, while 241 were downregulated. Many of these proteins were associated with mitochondria and metabolism, especially iron metabolism, indicating that legumain may have a previously unknown impact on related processes. Furthermore, we used N-terminomics/TAILS (terminal amine isotopic labeling of substrates) to identify potential substrates of legumain. We identified three new proteins that are cleaved after asparagine residues, which may reflect legumain-dependent cleavage. We confirmed that frataxin, a mitochondrial protein associated with the formation of iron-sulfur clusters, can be cleaved by legumain. This further asserts a potential contribution of legumain to mitochondrial function and iron metabolism. Lastly, we also identified a potential new cleavage site within legumain itself that may give rise to a 25 kDa form of legumain that has previously been observed in multiple cell and tissue types. Collectively, these data shed new light on the potential functions of legumain and will be critical for understanding its contribution to disease.


Asunto(s)
Cisteína Endopeptidasas/química , Mitocondrias/metabolismo , Péptidos/genética , Proteómica , Animales , Asparagina/química , Asparagina/genética , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Regulación de la Expresión Génica/genética , Humanos , Hierro/metabolismo , Marcaje Isotópico , Macrófagos/química , Macrófagos/metabolismo , Ratones , Mitocondrias/genética , Péptidos/química , Células RAW 264.7
19.
Clin Infect Dis ; 71(7): e141-e150, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-31712802

RESUMEN

BACKGROUND: Carbapenemase-producing Klebsiella pneumoniae has become a global priority, not least in low- and middle-income countries. Here, we report the emergence and clinical impact of a novel Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP) sequence type (ST) 16 clone in a clonal complex (CC) 258-endemic setting. METHODS: In a teaching Brazilian hospital, a retrospective cohort of adult KPC-KP bloodstream infection (BSI) cases (January 2014 to December 2016) was established to study the molecular epidemiology and its impact on outcome (30-day all-cause mortality). KPC-KP isolates underwent multilocus sequence typing. Survival analysis between ST/CC groups and risk factors for fatal outcome (logistic regression) were evaluated. Representative isolates underwent whole-genome sequencing and had their virulence tested in a Galleria larvae model. RESULTS: One hundred sixty-five unique KPC-KP BSI cases were identified. CC258 was predominant (66%), followed by ST16 (12%). The overall 30-day mortality rate was 60%; in contrast, 95% of ST16 cases were fatal. Patients' severity scores were high and baseline clinical variables were not statistically different across STs. In multivariate analysis, ST16 (odds ratio [OR], 21.4; 95% confidence interval [CI], 2.3-202.8; P = .008) and septic shock (OR, 11.9; 95% CI, 4.2-34.1; P < .001) were independent risk factors for fatal outcome. The ST16 clone carried up to 14 resistance genes, including blaKPC-2 in an IncFIBpQIL plasmid, KL51 capsule, and yersiniabactin virulence determinants. The ST16 clone was highly pathogenic in the larvae model. CONCLUSIONS: Mortality rates were high in this KPC-KP BSI cohort, where CC258 is endemic. An emerging ST16 clone was associated with high mortality. Our results suggest that even in endemic settings, highly virulent clones can rapidly emerge demanding constant monitoring.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Adulto , Antibacterianos , Proteínas Bacterianas/genética , Brasil/epidemiología , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Tipificación de Secuencias Multilocus , Estudios Retrospectivos , beta-Lactamasas/genética
20.
J Surg Oncol ; 121(5): 718-729, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31777095

RESUMEN

BACKGROUND AND OBJECTIVES: The primary treatment for locally advanced cases of cervical cancer is chemoradiation followed by high-dose brachytherapy. When this treatment fails, pelvic exenteration (PE) is an option in some cases. This study aimed to develop recommendations for the best management of patients with cervical cancer undergoing salvage PE. METHODS: A questionnaire was administered to all members of the Brazilian Society of Surgical Oncology. Of them, 68 surgeons participated in the study and were divided into 10 working groups. A literature review of studies retrieved from the National Library of Medicine database was carried out on topics chosen by the participants. These topics were indications for curative and palliative PE, preoperative and intraoperative evaluation of tumor resectability, access routes and surgical techniques, PE classification, urinary, vaginal, intestinal, and pelvic floor reconstructions, and postoperative follow-up. To define the level of evidence and strength of each recommendation, an adapted version of the Infectious Diseases Society of America Health Service rating system was used. RESULTS: Most conducts and management strategies reviewed were strongly recommended by the participants. CONCLUSIONS: Guidelines outlining strategies for PE in the treatment of persistent or relapsed cervical cancer were developed and are based on the best evidence available in the literature.


Asunto(s)
Exenteración Pélvica/normas , Neoplasias del Cuello Uterino/cirugía , Anastomosis Quirúrgica , Brasil , Colostomía/métodos , Diagnóstico por Imagen , Drenaje , Femenino , Humanos , Laparoscopía , Escisión del Ganglio Linfático , Evaluación Nutricional , Estomía , Cuidados Paliativos , Diafragma Pélvico/cirugía , Lavado Peritoneal , Cuidados Posoperatorios , Cuidados Preoperatorios , Sociedades Médicas , Colgajos Quirúrgicos , Catéteres Urinarios , Reservorios Urinarios Continentes , Vagina/cirugía , Grabación en Video
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